Shoes, particularly athletic shoes, generally have an insole placed within the foot-receiving compartment when sold. The insole is positioned so that the user's foot will rest thereon while wearing the shoe. Generally, such insoles are removable and may be replaced with insoles which may employ various features of benefit to the user or the particular needs of the user's feet.
Wearing shoes may cause the temperature of the wearer's feet to rise. The feet can even become hot, particularly if the wearer is exercising. A normal bodily reaction to overheating is sweating. Thus, on occasion, a user's foot is hot and releases fluid in the form of sweat. While the foot is wearing the shoe, the heat and sweat can cause discomfort, odor, and other undesirable results.
On other occasions, in certain weather conditions, or due to the nature of a user's body temperature, feet can become chilled even while wearing shoes and additional warmth to the feet is needed.